Gauging device for buttonhole-stitching machines



E. B. ALLEN. GAuc-wc DEVICE FOR Bu-rToNHoL'E STITCHING MACHINES.

FILED FEB. 5. 1921- 2 SHEETSSHEET I WITN ESSES:

zw/M a ATTORNEY H INVENTOR E. B. ALLEN,

Jan. 23, 1923.

2 SHEETS-SHEET 2 GAuG NG DEVICE FOR BUTTONHOLE ST ITCH NG MACHINES Fl LED FEB 5. 1 921 INVENTOR 5W4 e BY gig V WITNESSES:

/ ATTORNEY Wad/0 10 Patented Jan. 23, 1923.

- NITED. s r ,1;

EDWARD B. ALLEN, E NEWTOWN, CONNECTICUT, ASSIGNOR TO THE SINGER MANU- FACTURING COMPANY, OI ELIZABETH, JERSEY, A CORPORATION OF NEW JERSEY.

GAUGI NG DEVICE FOR BUTTONITiOLE-STITCHING MACHINES.

Application filed February 5, 1921. Serial No. 442,607.

To all 1 720m it may concern 'Be itknown that LFnwARn AL EN, a citizenof the United States, residing at Newtown, in the county of Fairfield and 5 State ofConnecticut, have invented certain new and useful Improvements in Gauging Devices for Buttonhole-Stitching Machines,

of which the following is a specification,

reference being; had therein to the accoln panying; drawings. i i

This invention relates to sewing machines more particularly of the automatic type adaptedto sew a group of a predetermined number of stitches. Machines of this type are commonly employedfci; sewing bartacks across the ends of pockets, buttonholes andthe like. An object 0t the present invention is to provide a machine of this class described with animproved gauging', device which will enable the operator to quickly and accurately position in the work-clamp the slitted work or buttonhole to be tacked or finished, whereby the group of finishing. stitchesor bar tack may be symmetrically placed across the end of the slit in the work and, in the case of a buttonhole finishing machine, to insure that the finishing stitches will bind in the ends of the cord or gimp and the ends of the threads of the buttonhol e overseam. 7

"Another object of the invention is to provide a gauging device which will handle butto iholesfof various sizes with equal facility without requiringadjustment.

While buttonhole gauges for finishing machines have heretofore been proposed, considerabledifiiculty has been experienced in securing their use uniformly satisfactory resultsfinasmuch as no prior gauge with 40' which I ain familiar is adapted to engage the huttonhole' at the extreme unfinished end of the'buttonholeslit and remain in gaugiii position to accurately locate such endin' he work-clamp within the range of action of the stitch-forming mechanism ntiYt-he clamp has been firmly closed upon assi nies control of the work.

accordance with the present improvement, the gauging device, which preferably 50 is in thetorm of a fin or vertical blade, pre- Shuts alth i fver qa isdge into engas newness Xt -em je d 915 th li in t e work or the unfinished end of the stitched buttonhole is placed by the operator to accurately locate the end of the slit inthe work-clamp of the finishing machine. The guide-fin is preferably mounted upon the work-holder of the machine and the vertical edge at the end of the guide-fin is positioned substantially at the sewing point of the ma chine so that the finishing stitches or bartack will be located at the end of the slit in the work without leaving an unsightly space between the end of the slit and the bar-tack. Means are preferably provided for withdrawing the gauge from effective position after the worleclamp has been closed, whereby to avoid possible interference between the gauge and the needle during the sewing. Preferably,the gauge is slidably mounted lengthwise of the workholder and is adapted to be projected into and withdrawn from gauging position, preferably automatically, "asby means of a connect-ionj with 'anactuating element on the usual'pattern-cam or feed wheel. It is preferred to so time the movements of the gauge that it will be withdrawn from gaugingposition before the first stitch is corn pl'eted and will not be projected into gauginn position until the last stitch is being formed. Inasmuch as the first and last stitches are usually formed at one end of the bar or tack, there will be no interference of the gauge with the needle at these times.

In the accompanying'idrawings, Fig. 1 is a perspective view of a machine embodying the invention and adapted for the work of finishing buttonholes. Fig. 2 is a'vertical longitudinal section" through the stud-pin 40, Fig. 1. Fig. 3' is a plan view of the work-clamp and gauge elements, with the work in position. "'Fig. 4 is a similar view of the lower clamp-plate and gauge; the upper clamp f oot and work having been removed. 5 is a section on the line 5, 5, Fig.3. Fig. 6 is a section substantially on the line 6- 6. Fig. 1. Fig. 7 is anenlarged view of the end of a buttonhole as finished by the bar-tack producedby the machine and Fig. dis a diagrammatic view illustrating the arrangement of the consecutive stitches of thetackf' Inthe' "preferred embodiment of the invention, as illustrated, the machine proper is of the well known Singer class 68 type represented, for example, in the United States patents to Barron No. 1,093,241 of April 14, 1914 and No. 1,194,588 of August 15, 1916, and constructed with the bed 1, standard 2, overhanging bracket-arm 3 and head 4 in which is journaled the reciprocating needle-bar 5 carrying the needle 6 which cooperates with the usual loop-taker beneath the bed 1 to form stitches. The main driving shaft of the machine carries at its rear end the tight and loose pulleys 7 and 8 over which runs a belt controlled by the usual belt-shipper 9 forming a part of the usual stop-motion device 10 more fully represented in the first mentioned Barron patent. Machines of this type commonly embody a pattern-cam 'or feed-wheel 11 having grooves 12 and 13 in its inner and outer faces, respectively. The inner groove 12 customarily actuates a suitable follower lever 14 which through the usual connections impart-s longitudinal motion to the workholder supporting bar 15. The outer groove 13 customarily actuates a suitable follower lever 16 which through the usual connectionsimparts transverse components of motion to the work-holder supporting bar 15. Thework-holder may be of the usual form comprising the work-holder supporting bar carrying at its front end the lower work clamping element or plate 17. The upper clamping element is in the form of a foot 18 having a rectangular needle opening 19 and a clearance slOt 20 extending from the opening 19 into the shank 21 which is mounted for vertical movement in the head 22 and is pressed downwardly by a spring (not shown) within said head. The head 22 is carried by the bracket 23 rising from the rearward end of the bar 15. The foot 18 may be raised in the usual manner to permit removal and insertion of the work by. means of the presser-foot lifting lever 24 which lifts the presser-bar 25 carrying at its lower end the lateral bent arm 26 extending beneath the lateral pin 27 carried by the shank 21' of the foot 18. I

' The buttonhfole gauging device with which the present improvement is particularly concerned comprises, in its preferred embodiment, a vertlcal blade or guide-fin 28 cartried at the forward or free end of a thin fiat arm 29 disposed above the work-holder supporting bar 15 and adjustably secured by screw and slot connections 30, 30 upon the carrier-bar 31 superposed upon the work holder supportlng bar and grooved on its under side to form side flanges 32, 32, Fig.

. 6, adapted to engage the sides of the workholder supporting bar 15 and guide the carrier-bar 31 in its movement lengthwise of the bar 15. The bar 31 is formed with a longitudinal slot 33 through which passes seam threads 6.

the screw 34 threaded into the bar 15 and serving to hold the bar 31 slidably. in position upon the bar 15. 1 a

At its rearward end the bar 31 has mounted thereon an extension-piece 35 formed at itsforward end with an ear 36 which is con nected by means of a spring 37 to the bracket 23. At its rearward end, the extension-piece 35 terminates within the range of the lower end of a vibratory lever 38 pivotally mounted at its upper end upon the stud-pin 40, Figs. 1 and 2, carried by the bracket-arm The lever 38 is formed intermediate its ends with a short arm or lateral extension 41 which bears upon the peripheral surface of the feed-wheel 11; being held thereagainst by the spring 37 when the gauge 28 is in re tracted or dotted line position, Figs. 1 and 5. The feed-wheel 11 carries a stud-pin 42, in the path of movement of which lies the arm 41. hen the pin 42 strikes the arm 41, the lever 38 is shifted from dotted to full line position, Fig. 1, and the gauge 28 is pro- :jected to gauging position substantially at sewing position; such position being indicated by the dotted rectangle 43, Fig. 3. When the pin 42 passes beyond the arm 41 the spring 37 withdraws the gauge to ineffective or dotted line position removed 'from the aperture 19. q 7

. \Vhen the machine is arrested by the stopmotion device 10, the needle 6 is in raised position and the pin 42 is in engagement with the arm. 41 thereby holding the gauge 28 in gaugingor full lineposition. The upper clamping member may be lifted to permit the placing of the slitted work or buttonhole over the fin 28 with the unfinished end 44 of the slit, Fig. 5, in engagement with the vertical-edge 45 of the gauge 28 whichlocatesthe end 44substantially at the stitching point. The gauge 28 remains in gauging position until thefoot 18 is lowered and the work securely clamped in an accurately located position. The gauge may be withdrawn by any suitable means after the work is securely clamped. It is preferred to utilize the automatic means described for withdrawing the gauge. In the embodiment of the invention illustrated, when the machine is started, the needle makes the first stitch 1 at one end of the bar-tack and before the needle descends the second time, the pin 42vhaslpassed beyond the extension 41 of the lever 38, thus permitting the retraction of the gauge 28 from the stitching point by the spring 37. The needle first lays a plurality of long stitches a across the end'of the buttonholeslit 5. The needle then lays a series of short stitches c in zigzag arrangement covering the long stitches b and binding down the free ends of the gimp d and the ends ofthe over Thus no appreciable space appears between the end of the slit 5 and the bar-tack to mar th finished appearance of the work.

' been started.

. 2. In a sewing machine, the combination with a main shaft, stitch-forming mechanism, a work-holder, and means for relatively moving the stitch-forming mechanism and work holder to sew a group of stitches, of a work-slit positioning gauge within the field of ac'tionof the stitch-forming mechanism, means for shifting said gauge to a position removed from said field of action, and means connected to the mainshaft for timing the action of the gauge shifting means.

3. In a sewing machine, the combination with stitch-forming mechanism, a workholder, 21- feed-wheel and connections for relatively moving them to sew a group of stitches, of a work-slit positioning gauge located in sewing position, and means controlled by the feed-wheel for shifting said gauge to a position removed from sewing position upon starting the stitch-forming mechanism.

i 4. In a buttonhole finishing machine, in combination, stitch-forming mechanism, a work-clamp including separable upper and lower members, means for relatively moving are air the stitch-forming mechanism and the workclamp to sew a group of tacking stitches, a buttonhole positioning gauge adapted to remain in buttonhole locating position within the range of action of the stitch-forming mechanism until the work is gripped by the work-clamp, and means for thereafter withdrawing said gauge to a position beyond the range of action of the stitch-forming mechanism.

5. In a sewing machine, in combination, stitch-forming mechanism, a work-holder, a feed-wheel and connections for relatively moving the stitch-forming mechanism and I work-holder to sew a group of finishing stitches, a work-positioning gauge, and means controlled by the feed-wheel for shifting said gauge out of gauging position.

6. In a sewing machine, in combination, stitch-forming mechanism, a work-holder, a feed-wheel and connections for relatively moving the stitclrforming mechanism and work-holder to sew a group of finishing stitches, a work-positioning gauge, and means controlled by the feed-wheel for shifting said gauge into and out of gauging position.

7. In a sewing machine, the combination with stitch-forming mechanism and a work clamp relatively movable to sew a group of a predetermined number of stitches, of a gauge adapted to engage the unfinished end of a slit in the work and position it substantially at the sewing point until the work clamp is closed, and means for withdrawing the gauge from the sewing point after the work-clamp is closed.

In testimony whereof, I have signed my name to this specification.

EDWARD B. ALLEN. 

